jackwsmeter.c

   1 /*
   2  * jackwsmeter - jack meter over websockets
   3  *
   4  * Copyright (C) 2014 Frederic Peters <fpeters@0d.be>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 of the
   9  * License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public
  17  * License along with this program; if not, see
  18  * <http://www.gnu.org/licenses/>.
  19  */
  20
  21 /*
  22  * based on code,
  23  * from the libwebsockets test server: LGPL 2.1
  24  *   Copyright (C) 2010-2011 Andy Green <andy@warmcat.com>
  25  * from jackmeter, GPL 2+
  26  *   Copyright (C) 2005  Nicholas J. Humfrey
  27  */
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <unistd.h>
  32 #include <getopt.h>
  33 #include <string.h>
  34 #include <sys/time.h>
  35 #include <assert.h>
  36 #include <syslog.h>
  37 #include <math.h>
  38
  39 #include <signal.h>
  40
  41 #include <libwebsockets.h>
  42
  43 #include <jack/jack.h>
  44
  45 int max_poll_elements;
  46
  47 struct pollfd *pollfds;
  48 int *fd_lookup;
  49 int count_pollfds;
  50 int num_meters = 0;
  51
  52 int force_exit = 0;
  53
  54 #define MAX_METERS 10
  55
  56 float bias = 1.0f;
  57 float peaks[MAX_METERS];
  58 float sent_peaks[MAX_METERS];
  59
  60 jack_port_t *input_ports[MAX_METERS];
  61 jack_client_t *client = NULL;
  62
  63
  64 /* Read and reset the recent peak sample */
  65 static void read_peaks()
  66 {
  67         memcpy(sent_peaks, peaks, sizeof(peaks));
  68         memset(peaks, 0, sizeof(peaks));
  69 }
  70
  71
  72 /* this protocol server (always the first one) just knows how to do HTTP */
  73
  74 static int callback_http(struct libwebsocket_context *context,
  75                 struct libwebsocket *wsi,
  76                 enum libwebsocket_callback_reasons reason, void *user,
  77                                                            void *in, size_t len)
  78 {
  79         int m;
  80         int fd = (int)(long)user;
  81
  82         switch (reason) {
  83         case LWS_CALLBACK_HTTP:
  84                 if (libwebsockets_serve_http_file(context, wsi, "jackwsmeter.html", "text/html"))
  85                         return 1; /* through completion or error, close the socket */
  86
  87                 break;
  88
  89         case LWS_CALLBACK_HTTP_FILE_COMPLETION:
  90                 return 1;
  91
  92         case LWS_CALLBACK_ADD_POLL_FD:
  93
  94                 if (count_pollfds >= max_poll_elements) {
  95                         lwsl_err("LWS_CALLBACK_ADD_POLL_FD: too many sockets to track\n");
  96                         return 1;
  97                 }
  98
  99                 fd_lookup[fd] = count_pollfds;
 100                 pollfds[count_pollfds].fd = fd;
 101                 pollfds[count_pollfds].events = (int)(long)len;
 102                 pollfds[count_pollfds++].revents = 0;
 103                 break;
 104
 105         case LWS_CALLBACK_DEL_POLL_FD:
 106                 if (!--count_pollfds)
 107                         break;
 108                 m = fd_lookup[fd];
 109                 /* have the last guy take up the vacant slot */
 110                 pollfds[m] = pollfds[count_pollfds];
 111                 fd_lookup[pollfds[count_pollfds].fd] = m;
 112                 break;
 113
 114         case LWS_CALLBACK_SET_MODE_POLL_FD:
 115                 pollfds[fd_lookup[fd]].events |= (int)(long)len;
 116                 break;
 117
 118         case LWS_CALLBACK_CLEAR_MODE_POLL_FD:
 119                 pollfds[fd_lookup[fd]].events &= ~(int)(long)len;
 120                 break;
 121
 122         default:
 123                 break;
 124         }
 125
 126         return 0;
 127 }
 128
 129 static int
 130 callback_meter(struct libwebsocket_context *context,
 131                 struct libwebsocket *wsi,
 132                 enum libwebsocket_callback_reasons reason,
 133                 void *user, void *in, size_t len)
 134 {
 135         int n;
 136         int i;
 137         float db;
 138         char one_peak[100];
 139         char buf[LWS_SEND_BUFFER_PRE_PADDING + 512 + LWS_SEND_BUFFER_POST_PADDING];
 140         char *p = &buf[LWS_SEND_BUFFER_PRE_PADDING];
 141
 142         switch (reason) {
 143
 144         case LWS_CALLBACK_ESTABLISHED:
 145                 break;
 146
 147         case LWS_CALLBACK_SERVER_WRITEABLE:
 148                 p[0] = '\0';
 149                 for (i=0; i<num_meters; i++) {
 150                         db = 20.0f * log10f(sent_peaks[i] * bias);
 151                         snprintf(one_peak, 100, "%f ", db);
 152                         strcat((char*)p, one_peak);
 153                 }
 154                 n = strlen(p) + 1;
 155                 n = libwebsocket_write(wsi, (unsigned char*)p, n, LWS_WRITE_TEXT);
 156                 if (n < 0) {
 157                         lwsl_err("ERROR %d writing to socket\n", n);
 158                         return 1;
 159                 }
 160                 break;
 161
 162         default:
 163                 break;
 164         }
 165
 166         return 0;
 167 }
 168
 169 /* list of supported protocols and callbacks */
 170
 171 static struct libwebsocket_protocols protocols[] = {
 172         /* first protocol must always be HTTP handler */
 173
 174         {
 175                 "http-only",            /* name */
 176                 callback_http,          /* callback */
 177                 0,                      /* per_session_data_size */
 178                 0,                      /* max frame size / rx buffer */
 179         },
 180         {
 181                 "jack-wsmeter-protocol",
 182                 callback_meter,
 183                 0,
 184                 0,
 185         },
 186         { NULL, NULL, 0, 0 } /* terminator */
 187 };
 188
 189 void sighandler(int sig)
 190 {
 191         force_exit = 1;
 192 }
 193
 194 static struct option options[] = {
 195         { "help",       no_argument,            NULL, 'h' },
 196         { "debug",      required_argument,      NULL, 'd' },
 197         { "port",       required_argument,      NULL, 'p' },
 198         { "ssl",        no_argument,            NULL, 's' },
 199         { "interface",  required_argument,      NULL, 'i' },
 200         { "closetest",  no_argument,            NULL, 'c' },
 201 #ifndef LWS_NO_DAEMONIZE
 202         { "daemonize",  no_argument,            NULL, 'D' },
 203 #endif
 204         { NULL, 0, 0, 0 }
 205 };
 206
 207
 208 /* Callback called by JACK when audio is available.
 209    Stores value of peak sample */
 210 static int process_peak(jack_nframes_t nframes, void *arg)
 211 {
 212         unsigned int i, port;
 213
 214         for (port = 0; port < num_meters; port++) {
 215                 jack_default_audio_sample_t *in;
 216
 217                 /* just incase the port isn't registered yet */
 218                 if (input_ports[port] == 0) {
 219                         break;
 220                 }
 221
 222                 in = (jack_default_audio_sample_t *) jack_port_get_buffer(input_ports[port], nframes);
 223
 224                 for (i = 0; i < nframes; i++) {
 225                         const float s = fabs(in[i]);
 226                         if (s > peaks[port]) {
 227                                 peaks[port] = s;
 228                         }
 229                 }
 230         }
 231
 232         return 0;
 233 }
 234
 235
 236 /* Close down JACK when exiting */
 237 static void cleanup()
 238 {
 239         const char **all_ports;
 240         unsigned int i;
 241
 242         lwsl_debug("cleanup()\n");
 243
 244         for (i=0; i<num_meters; i++) {
 245                 all_ports = jack_port_get_all_connections(client, input_ports[i]);
 246
 247                 for (i=0; all_ports && all_ports[i]; i++) {
 248                         jack_disconnect(client, all_ports[i], jack_port_name(input_ports[i]));
 249                 }
 250         }
 251
 252         /* Leave the jack graph */
 253         jack_client_close(client);
 254
 255         closelog();
 256 }
 257
 258
 259 int main(int argc, char **argv)
 260 {
 261         int n = 0;
 262         int use_ssl = 0;
 263         struct libwebsocket_context *context;
 264         int opts = 0;
 265         char interface_name[128] = "";
 266         const char *iface = NULL;
 267 #ifndef WIN32
 268         int syslog_options = LOG_PID | LOG_PERROR;
 269 #endif
 270         unsigned int oldus = 0;
 271         struct lws_context_creation_info info;
 272
 273         int debug_level = 7;
 274 #ifndef LWS_NO_DAEMONIZE
 275         int daemonize = 0;
 276 #endif
 277
 278         jack_status_t status;
 279
 280         memset(&info, 0, sizeof info);
 281         info.port = 7681;
 282
 283         while (n >= 0) {
 284                 n = getopt_long(argc, argv, "ci:hsp:d:D", options, NULL);
 285                 if (n < 0)
 286                         continue;
 287                 switch (n) {
 288 #ifndef LWS_NO_DAEMONIZE
 289                 case 'D':
 290                         daemonize = 1;
 291                         syslog_options &= ~LOG_PERROR;
 292                         break;
 293 #endif
 294                 case 'd':
 295                         debug_level = atoi(optarg);
 296                         break;
 297                 case 's':
 298                         use_ssl = 1;
 299                         break;
 300                 case 'p':
 301                         info.port = atoi(optarg);
 302                         break;
 303                 case 'i':
 304                         strncpy(interface_name, optarg, sizeof interface_name);
 305                         interface_name[(sizeof interface_name) - 1] = '\0';
 306                         iface = interface_name;
 307                         break;
 308                 case 'h':
 309                         fprintf(stderr, "Usage: jackwsserver "
 310                                         "[--port=<p>] [--ssl] "
 311                                         "[-d <log bitfield>] <port>+\n");
 312                         exit(1);
 313                 }
 314         }
 315
 316 #if !defined(LWS_NO_DAEMONIZE)
 317         /*
 318          * normally lock path would be /var/lock/jwsm or similar, to
 319          * simplify getting started without having to take care about
 320          * permissions or running as root, set to /tmp/.jwsm-lock
 321          */
 322         if (daemonize && lws_daemonize("/tmp/.jwsm-lock")) {
 323                 fprintf(stderr, "Failed to daemonize\n");
 324                 return 1;
 325         }
 326 #endif
 327
 328         signal(SIGINT, sighandler);
 329
 330         /* we will only try to log things according to our debug_level */
 331         setlogmask(LOG_UPTO (LOG_DEBUG));
 332         openlog("jackwsmeter", syslog_options, LOG_DAEMON);
 333
 334         /* tell the library what debug level to emit and to send it to syslog */
 335         lws_set_log_level(debug_level, lwsl_emit_syslog);
 336
 337         max_poll_elements = getdtablesize();
 338         pollfds = malloc(max_poll_elements * sizeof (struct pollfd));
 339         fd_lookup = malloc(max_poll_elements * sizeof (int));
 340         if (pollfds == NULL || fd_lookup == NULL) {
 341                 lwsl_err("Out of memory pollfds=%d\n", max_poll_elements);
 342                 return -1;
 343         }
 344
 345         info.iface = iface;
 346         info.protocols = protocols;
 347 #ifndef LWS_NO_EXTENSIONS
 348         info.extensions = libwebsocket_get_internal_extensions();
 349 #endif
 350         if (!use_ssl) {
 351                 info.ssl_cert_filepath = NULL;
 352                 info.ssl_private_key_filepath = NULL;
 353         } else {
 354                 /*
 355                 info.ssl_cert_filepath = LOCAL_RESOURCE_PATH"/libwebsockets-test-server.pem";
 356                 info.ssl_private_key_filepath = LOCAL_RESOURCE_PATH"/libwebsockets-test-server.key.pem";
 357                 */
 358         }
 359         info.gid = -1;
 360         info.uid = -1;
 361         info.options = opts;
 362
 363         // Register with Jack
 364         if ((client = jack_client_open("wsmeter", JackNullOption, &status)) == 0) {
 365                 lwsl_err("Failed to start jack client: %d\n", status);
 366                 exit(1);
 367         }
 368         lwsl_debug("Registering as '%s'.\n", jack_get_client_name( client ) );
 369
 370         // Register the cleanup function to be called when program exits
 371         atexit( cleanup );
 372
 373         // Register the peak signal callback
 374         jack_set_process_callback(client, process_peak, 0);
 375
 376
 377         if (jack_activate(client)) {
 378                 lwsl_err("Cannot activate client.\n");
 379                 exit(1);
 380         }
 381
 382         opts = 1;
 383         num_meters = 0;
 384         while (argv[opts]) {
 385                 char in_name[255];
 386                 jack_port_t *port;
 387                 // Create our input port
 388                 snprintf(in_name, 255, "wsmeter_%d", num_meters);
 389                 if (!(input_ports[num_meters] = jack_port_register(client, in_name,
 390                                                 JACK_DEFAULT_AUDIO_TYPE, JackPortIsInput, 0))) {
 391                         lwsl_err("Cannot register input port '%s'.\n", in_name);
 392                         exit(1);
 393                 }
 394
 395                 port = jack_port_by_name(client, argv[opts]);
 396                 if (port == NULL) {
 397                         lwsl_err("Can't find port '%s'\n", argv[opts]);
 398                 } else {
 399                         if (jack_connect(client, jack_port_name(port), jack_port_name(input_ports[num_meters]))) {
 400                                 lwsl_err("failed to connect to port '%s'\n", argv[opts]);
 401                                 exit(1);
 402                         }
 403                 }
 404                 num_meters += 1;
 405                 opts++;
 406         }
 407
 408         if (num_meters == 0) {
 409                 lwsl_err("You must specify at least one port, aborting.");
 410                 exit(1);
 411         }
 412
 413         context = libwebsocket_create_context(&info);
 414         if (context == NULL) {
 415                 lwsl_err("libwebsocket init failed\n");
 416                 return -1;
 417         }
 418
 419         n = 0;
 420         while (n >= 0 && !force_exit) {
 421                 struct timeval tv;
 422
 423                 gettimeofday(&tv, NULL);
 424
 425                 read_peaks();
 426
 427                 /*
 428                  * This provokes the LWS_CALLBACK_SERVER_WRITEABLE for every
 429                  * live websocket connection using the DUMB_INCREMENT protocol,
 430                  * as soon as it can take more packets (usually immediately)
 431                  */
 432
 433                 if (((unsigned int)tv.tv_usec - oldus) > 100000) {
 434                         libwebsocket_callback_on_writable_all_protocol(&protocols[1]);
 435                         oldus = tv.tv_usec;
 436                 }
 437
 438                 n = poll(pollfds, count_pollfds, 25);
 439                 if (n < 0)
 440                         continue;
 441
 442
 443                 if (n)
 444                         for (n = 0; n < count_pollfds; n++)
 445                                 if (pollfds[n].revents)
 446                                         if (libwebsocket_service_fd(context,
 447                                                                   &pollfds[n]) < 0)
 448                                                 goto done;
 449
 450
 451                 n = libwebsocket_service(context, 25);
 452         }
 453
 454 done:
 455         libwebsocket_context_destroy(context);
 456
 457         lwsl_notice("jackwsserver exited cleanly\n");
 458
 459         return 0;
 460 }